I was working on a project made by someone else. It has above mentioned LCD display which is used in 4-bit character display mode and interfaced with a PIC microcontroller. The display was working fine. One day, i unplugged interface connectors (4-pin & 8-pin molex) of display to do some work on main board. I re-connect LCD connectors after i finish the work on main board. Unfortunately, I mis-aligned 4-pin (DB7-DB4/LCD pins 11-14) connecter with an offset of one space. I powered on the system and the display was gone. Only background light is visible. Now upon start-up, LCD displays black boxes for a while in upper row and then turns white. My initial guess was that the LCD is broken. I ordered a new LCD and replaced the old one. Still I have no luck with the new LCD. I donít know why it is not working?

Thank you for reply. I connected display and power up the system. I noticed the blank display and switched off the system immediately. UART of microcontroller is still working. I verified that throught hyper terminal. I am not sure if the pins connected to the datalines of display are ok ? Is their any way to check them ? You think any misalignemt of data lines can end into broken microcontroller pin ?